Objective To investigate the acute myocardial infarction (AMI) patient's electrocardiogram appearing fragment QRS wave (fQRS) and brain natriuretic peptide (BNP) level and scope of coronary lesions,severe cardiac complications,and the cor relation of cardiac death.Methods For selected patients with AMI,whether based on electrocardiogram (ECG) appeared in fQRS group and non fQRS groups; immunofluorescence technique was used to detect the plasma BNP level in patients with AMI.Two groups of patients with serious cardiac events and coronary artery lesions scope were observed; Coronary artery lesion count and BNP level were recorded.Results The incidence of fragment QRS wave in patients with AMI was 34.0％,fQRS wave group height/three degree atri oventricular block,ventricular tachycardia/ventricular fibrillation,cardiac shock,cardiac death rate was higher than non fQRS wave group (P ＜0.05).fQRS wave group of plasma BNP and left ventricular end-diastolic diameter,the double branch lesion,multivessel lesions were significantly higher than that of non fQRS group (P ＜ 0.01) ; left ventricular ejection fraction,the single lesion was sig nificantly lower than non fQRS wave group (P ＜0.01).The BNP levels in single,double,and multivessel lesions in the group with the increase of the lesion count were increased.Conclusions The AMI patients with fQRS easily complicated with severe arrhythmia,and case fatality rate was high,the prognosis was poor.fQRS on electrocardiogram (ECG) and BNP level had a certain relationship with range and degree of coronary artery lesions,degree of indexes might be used as a prediction of coronary lesions,and multivessel lesions had certain prediction value.